         best-char     (apply max-key char-bits avail-chars) ]
     best-char ) )
 
-(defn make-guess-freq
-  "Generate the next guess letter, based on letter frequencies in the surviving words. "
-  [keep-words used-chars]
-  (let [
-    col-char-freqs  (to-freqs-by-col keep-words)
-    all-char-freqs    (apply merge-with + col-char-freqs)
-    avail-chars       (set/difference (set(keys all-char-freqs)) used-chars)
-      ; _ (println "avail-chars" avail-chars )
-    max-avail-char    (apply max-key all-char-freqs avail-chars ) 
-  ] max-avail-char ) )
-
 (defn make-clue
   "Generate a clue given the target word and a vec of guessed letters."
   [target-vec guesses-set]

    (assert (= (get-array-col tstArr 2) [:c  3 \c] ))
  )

  ; Use of (frequencies...) and (merge-with...)
  (assert (= (frequencies "abbccc")          
             {\a 1, \b 2, \c 3} ))
  (assert (= (frequencies ["abc" "bc" "c"])  
             {"abc" 1 "bc" 1 "c" 1} ))
  (assert (= (map frequencies ["abc" "bc" "c"])
             [ {\a 1, \b 1, \c 1} {\b 1, \c 1} {\c 1} ] ))
  (assert (= (apply merge-with + (map frequencies ["abc" "bc" "c"]) )
             {\a 1 \b 2 \c 3} ))

  ; Match guesses
  (assert (guess-matches? "abcd" "abcd") )
  (assert (guess-matches? "abcd" [\a \b \c \d]) )

      _ (assert (= keep-words ["abcd" "xbcd"] ))
    guessed-chars       #{ \b }
      _ (assert (= guessed-chars #{\b} ))
  ] )
)

